Back in the 60's and early 70's, the recurve was the most technologically advanced bow until the compound started hitting the scene. The term "Traditional Archery" wasn't coined yet, so guys just gravitated toward what they thought was the best type of bow.
The resurgance of the longbow today is probably due to the romance of the thing, but then guys realized that they are very effective weapons. Heck, when I was a teenager in the late 1980s and early 1990s hardly anybody shot traditional bows where I grew up. One day at a 3D shoot, there were a couple of guys shooting traditional bows - one had a Black Widow and the other had a Howard Hill. I was amazed, but I think I insulted the guy with the longbow when I asked him if it had enough power to kill a deer. I was a dumb teenager.